Essential Idea:
Immunity is based on recognition of self
and destruction of foreign materials
Understandings:
- Every organism has unique molecules on the surface of its cells
- Pathogens can be species-specific although others can cross species barriers
- B lymphocytes are activated by T lymphocytes in mammals
- Activated B cells multiply to form clones of plasma cells and memory cells
- Plasma cells secrete antibodies
- Antibodies aid the destruction of pathogens
- White blood cells release histamine in response to allergens
- Histamine causes allergic symptoms
- Immunity depends on the persistance of memory cells
- Vaccines contain antigens that trigger immunity but do not cause the disease
- Fusion of a tumor cell with an antibody-producing cell creates a hybridoma cell
- Monoclonal antibodies are produced by hybridoma cells
Applications:
- Smallpox was the first infectious disease of humans to have been eradicated by vaccination
- Monoclonal antibodies to hCG are used in pregnancy test kits
- Antigens on the surface of red blood cells stimulate antibody production in a person with a different blood group
Skills:
- Analysis of epidemiological data related to vaccination programmes